The radiotherapy using a radiotherapy device, is to make the patient's targets rotatively irradiated as per the work principle of rotation focusing, with the target tissues at the rotary focus subjected to the maximum dose of radiation while the healthy tissues to an instantaneous tolerable dose of radiation, so as to kill the targets while sparing the surrounding healthy tissues. As a result, the aim of radiotherapy can be achieved. A radiotherapy device is disclosed in the patent of multi-source whole-body radiotherapy device with Chinese Patent Publication Number CN 1275410. The radiotherapy device includes a source carrier, a rotary ring fixed to the source carrier, a collimator carrier, a rotary ring fixed to the collimator carrier, a rotary support, and a fixed rotary support ring. Multiple rolling bearings are positioned between the rotary support ring and the rotary ring of the source carrier as well as between the rotary ring of the source carrier and that of the collimator carrier respectively, forming a rotary fit with axial localization. The source carrier and the collimator carrier can rotate around the same rotary axis respectively. Multiple radiation sources distributed in the source carrier focus and irradiate on a shared focus at the rotary axis through radiation channel in the source carrier and the collimator carrier. The collimator carrier is equipped with collimators, divided into groups as per different apertures. The collimators of each group are distributed in the same way as the radiation sources in the source carrier. The radiation sources and the radiation channel in the source carrier are distributed radially in a sectorial area with angle of less than 90 degrees, and axially in a sectorial area with angle of less than 60 degrees. Rotation of the collimator carrier relative to the source carrier can make the entrance of the collimators of each group align with the radiation sources in the source carrier, respectively. The collimators of different apertures can change the beam size of the radiation sources. The interior rotary radius of the collimator carrier is smaller than the human width.
The multiple radiation sources in the source carrier in the above device are therapeutic. If without a real-time imaging system, neither image detection nor monitoring of target motion nor verification of radiotherapy dose could be done during treatment, thus affecting the accuracy of coinciding the radioactive focusing center with the targets. So without it, the treatment plan couldn't be revised as per the actual radiation dose taken by patient, the precision radiotherapy couldn't be made, and radiotherapy result would be affected.
The rotary support of the above device is equipped inside with the rotary support ring, the rotary ring of the source carrier and that of the collimator carrier. Its shortcomings are the three inlaid slip-on rotary rings reduce the therapeutic space and the rotary scope of the collimator carrier, and increase manufacturing difficulty and cost.